Republic XF-91 Thunderceptor: Difference between revisions
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{{ |
{|{{Infobox Aircraft Begin |
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|name = |
|name =XF-91 Thunderceptor |
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|image =XF91-21republic.jpg |
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|type =Interceptor |
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|manufacturer =[[Republic Aviation Company]] |
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|image =Image:XF-91.jpg |
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|caption = |
|caption = |
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}}{{Infobox Aircraft Type |
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|type =Prototype interceptor aircraft |
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|manufacturer =[[Republic Aviation]] |
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|designer = |
|designer = |
||
|first flight = |
|first flight =9 May 1949 |
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|introduced = |
|introduced = |
||
|retired = |
|retired = |
||
|status = |
|status =Canceled |
||
|primary user = |
|primary user = |
||
|more users = |
|more users = |
||
|produced = |
|produced = |
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|number built =2 |
|number built =2 |
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|unit cost =US$11.6 million for the program<ref name="knaack"> |
|unit cost ={{US$|link=yes}}11.6 million for the program<ref name="knaack">Knaack 1978, p. 309.</ref> |
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|developed from= [[Republic F-84 Thunderjet]] |
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|variants with their own articles = |
|variants with their own articles = |
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}} |
}} |
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|} |
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The ''' |
The '''Republic XF-91 Thunderceptor''' (originally designated '''XP-91''') was a mixed-propulsion [[prototype]] [[interceptor aircraft]], developed by [[Republic Aviation]]. The aircraft would use a [[jet engine]] for most flight, and a cluster of four small [[rocket engine]]s for added thrust during climb and interception. The design was largely obsolete by the time it was completed due to the rapidly increasing performance of contemporary jet engines, and only two prototypes were built. One of these was the first US fighter to exceed [[Mach (speed)|Mach]] 1 in level flight. |
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A unique feature of the Thunderceptor, which makes it instantly recognizable, is the odd wing planform which has much greater chord at the tips than the root, the opposite of typical [[swept wing]] designs. This was an attempt to address the problem of [[pitch-up]], a potentially deadly problem that plagued early high-speed designs. The Thunderceptor's design meant the entire wing [[Stall (flight)|stalled]] smoothly, more like a straight-wing design. |
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The Thunderceptor design was one of two [[swept-wing]] modifications based on the original [[F-84 Thunderjet]], the other being the F-84F ''Thunderstreak'' which happened later. A serious problem with most [[swept wing]] designs of the era was dangerous performance at low speeds and high [[angle of attack]]. The stagnant airflow over the wing tended to "slide" towards the wingtips, which caused them to [[stall]] before the rest of the wing at high angles of attack. In this situation the center of lift would rapidly shift forward relative to the center of mass, pitching the nose up and leading to an even greater angle of attack or, in extreme cases, end-over-end tumbling of the aircraft. Planes caught in this regime would often stall and crash, and a rash of such accidents on the [[F-86 Sabre]] led to the term [[Sabre dance]]. The most famous incident was the loss of F-100C-20-NA Super Sabre 54-1907 during an attempted emergency landing at Edwards AFB, California on January 10, 1956 which was caught by film cameras set up for an unrelated test. The pilot fought to retain control as he rode the knife-edge of the flight envelope but fell off on one wing, hit the ground and exploded with fatal results. |
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==Design and development== |
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The Thunderceptor's most notable design feature was intended to address this problem. The wings were built to have considerably more [[chord (aircraft)|chord]] (distance from front to back) at the tip than root, allowing them to generate more lift. This neatly addressed the problems with Sabre dance by delaying the point of stall on the tip to that of the entire wing. A side effect of this design was that the tips had more internal room, so the [[landing gear]] was mounted to retract outward with the wheels lying in the wingtips, using two small tires instead of one larger one. Another design change was the ability to vary the [[angle of incidence]] of the wing as a whole, tilting it up for low speed operations during takeoff and landing, and then "leveling it off" for high-speed flight and cruise. This allowed the fuselage to remain closer to level while landing, greatly improving visibility. |
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[[File:XF-91.jpg|thumb|XF-91 in 1951 at Edwards Air Force Base.]] |
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During the development of the XP-84, Republic, under the guidance of Alexander Kartveli looked at the installation of rockets to fighters. The company was inspired by German wartime aircraft: the rocket-powered [[Messerschmitt Me 163]] and the experimental [[Messerschmitt Me 262]]C ''Heimatschützer'' (home protector) series of [[Interceptor aircraft|interceptor]] prototypes, which added rocket boosters to a turbojet aircraft. |
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The Thunderceptor design was one of two [[swept-wing]] modifications based on the original [[Republic F-84 Thunderjet]], the other being the [[Republic F-84F Thunderstreak]] which was developed later. A serious problem with most [[swept wing]] designs of the era was dangerous performance at low speeds and high [[angle of attack]]. The stagnant airflow over the wing tended to "slide" towards the wingtips, which caused them to [[Stall (flight)|stall]] before the rest of the wing. In this situation the center of lift would rapidly shift forward relative to the center of mass, pitching the nose up and leading to an even greater angle of attack or, in extreme cases, end-over-end tumbling of the aircraft. Aircraft caught in this regime would often stall and crash, and a rash of such accidents with the [[North American F-100 Super Sabre]] led to the term [[Sabre dance (pitch-up)|"Sabre dance"]]. The most famous incident was the loss of an F-100C Super Sabre during an attempted emergency landing at Edwards AFB, California on 10 January 1956 which was caught by film cameras set up for an unrelated test. The pilot fought to retain control as he rode the knife-edge of the flight envelope but fell off on one wing, hit the ground and exploded with fatal results. |
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In keeping with its intended role as an interceptor, the nose was redesigned to incorporate [[radar]], forcing them to move the air intake for the engine from its original nose-mounted position to a new intake below it. The fuselage was otherwise very similar to the F-84's. The first prototype did not include the radome, although this was a part of the second prototype. |
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The Thunderceptor's most notable design feature was intended to address this problem. The wings were built to have considerably more [[chord (aircraft)|chord]] (distance from the leading edge to the trailing edge) at the tip than root, allowing them to generate more lift. This neatly addressed the problem of Sabre dance by delaying the point of stall on the tip to that of the entire wing. A side-effect of this design was that the tips had more internal room, so the [[landing gear]] was mounted to retract outwards with the wheels lying in the wingtips, using two smaller wheels in a [[tandem]] arrangement for each main gear strut, instead of one larger one. Another design change was the ability to vary the [[angle of incidence]] of the wing as a whole, tilting it up for low speed operations during takeoff and landing, and then "leveling it off" for high-speed flight and cruise. This allowed the fuselage to remain closer to level while landing, greatly improving visibility. |
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The first prototype made its first flight on [[May 9]], [[1949]], breaking the speed of sound in December 1951. It was later modified with a small radome for gunnery ranging (although not the "full" radome from the second prototype). The second prototype included the full radome and chin-mounted intake, but was otherwise similar. This airframe was later modified to use a [[V-tail]] for testing. With both the jet and rockets running, the plane could reach Mach 1.71, rather respectable for the early [[1950s]]. Both prototypes were used for testing for several years. |
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In keeping with its intended role as an interceptor, the nose was redesigned to incorporate a [[radar]] antenna, forcing the air intake for the engine to be moved from its original nose-mounted position to a new intake below it. The fuselage was otherwise very similar to the F-84's. The first prototype did not include the radome, although this was fitted to the second prototype. |
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As an interceptor the Thunderceptor was soon eclipsed by designs from other companies, but like the Thunderceptor none of these would go into production. The [[US Air Force]] decided to wait the short time needed to introduce newer and much more capable designs created as a part of the [[1954 Interceptor]] project. The Thunderceptor, like the other interceptor designs of the era, had extremely short flight times on the order of 25 minutes, making them almost useless for protecting an area as large as the United States. The 1954 designs outperformed the F-91 in speed, range, loiter time, and included the [[radar]] and [[fire-control system]]s needed for night and all-weather operation. The era of the dedicated [[day fighter]]-type interceptor were over. |
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==Testing and evaluation== |
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One XF-91, serial 46-680, is preserved at the [[National Museum of the United States Air Force]]. The second prototype, serial 46-681, was lost due to engine failure during take-off from Edwards AFB in the summer of 1951. [[Republic Aviation]] test pilot [[Carl Bellinger]] escaped from the aircraft just as the tail melted off — total flight time from take off to pilot evacuation was a mere ninety seconds. By the time fire apparatus arrived, driving seven miles across the dry lakebed, the airframe had been reduced to ashes. [[Chuck Yeager]] was flying chase in an F-86 Sabre on this brief flight. |
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[[File:Republic XF-91 banking away in flight.jpg|thumb|XF-91 Thunderceptor during testing]] |
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[[File:XF91-22republic.jpg|thumb|On the left is Republic XF-91 ([[United States military aircraft serials|S/N]] 46-680) after the nose radome installation and on the right is XF-91 ([[United States military aircraft serials|S/N]] 46-681) after the V-tail modification.]] |
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The first prototype made its first flight on 9 May 1949, breaking the speed of sound in December 1951. It was later modified with a small radome for gunnery ranging (although not the "full" radome from the second prototype). The second prototype included the full radome and chin-mounted intake, but was otherwise similar. With both the jet and rockets running, the aircraft could reach Mach 1.71. Both prototypes completed 192 test flights over the course of five years.<ref>Yenne 1993, p. 114.</ref> |
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The second prototype, ''46-681'', had an engine failure during takeoff from Edwards AFB in the summer of 1951. Republic test pilot [[Carl Bellinger]] escaped from the aircraft just as the tail melted off - total flight time was a mere 90 seconds. By the time fire apparatus arrived, driving seven miles across the dry lake bed, the tail section had been reduced to ashes. 46-681 was then fitted with a [[V-tail|"V"]] or "butterfly" tail, and was flight-tested with this configuration. It was later used at Edwards AFB as a crash-crew training simulator, then scrapped.<ref>Pace 1991, p. 87.</ref> |
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As an interceptor the Thunderceptor was soon eclipsed by designs from other companies, but like the Thunderceptor none of these would go into production. The [[United States Air Force]] decided to wait the short time needed to introduce newer and much more capable designs created as a part of the [[1954 interceptor]] project. The Thunderceptor, like the other interceptor designs of the era, had extremely short flight times on the order of 25 minutes, making them almost useless for protecting an area as large as the United States. The 1954 designs outperformed the XF-91 in speed, range, loiter time, as well as including the radar and [[fire-control system]]s needed for night and all-weather operation. The era of the dedicated [[day fighter]]-type interceptor was over. |
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==Aircraft disposition== |
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[[File:Republic XF-91.jpg|thumb|XF-91 Thunderceptor, s/n ''46-680'' on display]] |
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*46-0680 - Research & Development Gallery at the [[National Museum of the United States Air Force]] at [[Wright-Patterson AFB]] in [[Dayton, Ohio]].<ref>[http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=584 "XF-91 Thunderceptor/46-680"] ''National Museum of the United States Air Force.'' Retrieved: 13 June 2011.</ref> |
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*46-0681 - destroyed while testing at [[Edwards AFB]] in 1951.<ref>[http://www.joebaugher.com/usaf_serials/1946.html "XF-91 Thunderceptor/46-681."] ''Joe Baugher serial numbers.'' Retrieved: 10 May 2013.</ref> |
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==Specifications (XF-91 Thunderceptor)== |
==Specifications (XF-91 Thunderceptor)== |
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[[ |
[[File:XF-91 3-View line art.svg|right|300px]] |
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{{aircraft specifications| |
{{aircraft specifications| |
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|plane or copter?=plane |
|plane or copter?=plane |
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|jet or prop?= |
|jet or prop?=both |
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|ref={{citation needed|date=July 2011}} |
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|crew=1 |
|crew=1 |
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|length main=43 ft 3 in |
|length main=43 ft 3 in |
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| Line 50: | Line 69: | ||
|area main= 320 ft² |
|area main= 320 ft² |
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|area alt= 29.73 m² |
|area alt= 29.73 m² |
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|empty weight main=14,140 lb |
|empty weight main=14,140 lb |
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|empty weight alt=6,410 kg |
|empty weight alt=6,410 kg |
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| Line 57: | Line 75: | ||
|max takeoff weight main=28,300 lb |
|max takeoff weight main=28,300 lb |
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|max takeoff weight alt=12,840 kg |
|max takeoff weight alt=12,840 kg |
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|engine (jet)= [[General Electric J47|General Electric J47-GE-7 (later GE-17)]] |
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|engine (jet)= [[General Electric J47|General Electric J47-GE-3]] |
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|type of jet= axial-flow turbojet |
|type of jet= axial-flow turbojet |
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|number of jets=1 |
|number of jets=1 |
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|thrust main= 5,200 lbf |
|thrust main= 5,200 lbf |
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|thrust original=; 6,900 lbf with afterburning |
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|thrust alt= 23 kN))</li> |
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|thrust alt= 30,6 kN |
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<li>'''Powerplant:''' 4x [[Reaction Motors XLR11|Reaction Motors XLR11-RM-9]] rockets, 1,500 lbf (7 kN |
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|engine (prop)=[[Reaction Motors XLR11|Reaction Motors XLR11-RM-9]] |
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|type of prop= rocket |
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|max speed main=mph |
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|number of props=4 |
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|power main= 1,500 lbf |
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|power alt= 7 kN |
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|max speed main=984 mph |
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|max speed alt=1,584 km/h |
|max speed alt=1,584 km/h |
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|range main=1,170 mi |
|range main=1,170 mi |
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|range alt=1,880 km |
|range alt=1,880 km |
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|ceiling main=50,000 to 55,000 ft |
|ceiling main=50,000 to 55,000 ft |
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|ceiling alt=15,200 to 16,800 m |
|ceiling alt=15,200 to 16,800 m |
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|climb rate main= 47,500 ft in 2.5 minutes |
|climb rate main= 47,500 ft in 2.5 minutes |
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|climb rate alt= 14,500 m |
|climb rate alt= 14,500 m |
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|loading main= 58.12 lb/ft² |
|loading main= 58.12 lb/ft² |
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|loading alt= 283 kg/m² |
|loading alt= 283 kg/m² |
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|thrust/weight= 0.60 |
|thrust/weight= 0.60 |
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|guns=4 × 20 mm (.79 in) cannon |
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}} |
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==See also== |
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|armament= |
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{{Portal|Military of the United States|Aviation}} |
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* 4 x 20 mm cannon |
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{{aircontent| |
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|related= |
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|similar aircraft= |
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*[[Avro 720]] |
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*[[Saunders-Roe SR.53]] |
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*[[Saunders-Roe SR.177]] |
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|lists= |
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*[[List of military aircraft of the United States]] |
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*[[List of fighter aircraft]] |
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|see also= |
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}} |
}} |
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==References== |
==References== |
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<references/> |
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===Notes=== |
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{{cite book|author=Yeager, C. Janos, L.|title=Yeager|publisher=Bantam Books|year=1985|id=ISBN 0-553-05093-1}} |
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{{Reflist}} |
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===Bibliography=== |
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{{Refbegin}} |
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* Jenkins, Dennis R. and Tony R. Landis. ''Experimental & Prototype U.S. Air Force Jet Fighters.'' North Branch, Minnesota, USA: Specialty Press, 2008. ISBN 978-1-58007-111-6. |
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* Knaack, Marcelle Size.''Encyclopedia of US Air Force Aircraft and Missile Systems: Volume 1, Post-World War II Fighters, 1945-1973''. Washington, D.C.: Office of Air Force History, 1978. ISBN 0-912799-59-5. |
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* Pace, Steve. ''Republic XF-91 Thunderceptor Rocket Fighter'' (Air Force Legends N.210). Simi Valley, California, USA: Steve Ginter Books, 2000. ISBN 0-942612-91-4. |
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* Pace, Steve. ''X-Fighters: USAF Experimental and Prototype Fighters, XP-59 to YF-23''. St. Paul, Minnesota, USA: Motorbooks International, 1991. ISBN 0-87938-540-5. |
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* Winchester, Jim. ''The World's Worst Aircraft: From Pioneering Failures to Multimillion Dollar Disasters''. London: Amber Books Ltd., 2005. ISBN 1-904687-34-2. |
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* [[Chuck Yeager|Yeager, Chuck]] and Leo Janos. ''Yeager: An Autobiography''. New York: Bantam Books, 1986. ISBN 0-553-25674-2. |
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* Yenne, Bill. ''The World's Worst Aircraft''. New York: Dorset Press, 1993. ISBN 0-88029-490-6. |
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{{Refend}} |
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== Further reading == |
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* {{cite book |last= Pace |first= Steve |year= 2000 |title= Republic XF-91 Thunderceptor |edition= First |editor-first= |editor-last= |publisher= Ginter Books |series=Air Force Legends |volume=Nº210 |language= |url= http://www.ginterbooks.com/AIRFORCE/AF210.htm |isbn= 0-942612-91-4 |location= California, United States |accessdate= 1 February 2015 }} |
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==External links== |
==External links== |
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{{Commons category|Republic XF-91}} |
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===Descriptions=== |
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*[http://www.centennialofflight.gov/essay/Aerospace/Republic/Aero43G13.htm XF-91 in U.S Centennial of Flight Commission] |
*[http://www.centennialofflight.gov/essay/Aerospace/Republic/Aero43G13.htm XF-91 in U.S Centennial of Flight Commission] |
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*[http://www.ibiblio.org/pub/academic/history/marshall/military/airforce/f_series_fighters/f91 XF-91 in sci.military] |
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*[http://www.wpafb.af.mil/museum/annex/an3.htm XF-91 at the National Museum of the United States Air Force] |
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===Images=== |
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*[http://www.aerofiles.com/repub-xf91b.jpg XF-91b at www.aerophiles.com] |
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*[http://www.aerofiles.com/repub-xf91.jpg XF-91 at www.aerophiles.com] |
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*[http://1000aircraftphotos.com/Fairchild/5419.htm Several pictures of the XF-91 ''46-680''] |
*[http://1000aircraftphotos.com/Fairchild/5419.htm Several pictures of the XF-91 ''46-680''] |
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*[http://www.flightglobal.com/pdfarchive/view/1949/1949%20-%200431.html Interceptor, 1949] - pictures from ''Flight'' 1949 |
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{{Republic aircraft}} |
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==Related content== |
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{{USAF fighters}} |
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{{aircontent| |
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|related=<!-- related developments --> |
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|similar aircraft= |
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[[Saunders-Roe SR.53]] - [[Saunders-Roe SR.177]] |
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|sequence= |
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[[XF-88 Voodoo|XF-88]] - |
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[[F-89 Scorpion|F-89]] - |
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[[Lockheed XF-90|XF-90]] - |
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'''XF-91''' - |
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[[Convair XF-92|XF-92]] - |
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[[North American YF-93|YF-93]] - |
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[[Lockheed F-94|F-94]] |
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|lists= |
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[[List of military aircraft of the United States]] - [[List of fighter aircraft]] |
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|see also=<!-- other relevant information --> |
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}} |
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[[Category:Mixed-power aircraft]] |
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[[Category:U.S. fighter aircraft 1940-1949|F-91]] |
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[[Category:Rocket-powered aircraft]] |
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[[ |
[[Category:Republic aircraft|F-091]] |
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[[Category:United States fighter aircraft 1940–1949|Republic F-91]] |
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[[ja:XF-91 (戦闘機)]] |
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[[Category:Single-engined jet aircraft]] |
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[[Category:Aircraft with auxiliary rocket engines]] |
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[[Category:Monoplanes]] |
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Revision as of 04:38, 25 June 2015
| XF-91 Thunderceptor | |
|---|---|
| |
| Role | Prototype interceptor aircraft |
| Manufacturer | Republic Aviation |
| First flight | 9 May 1949 |
| Status | Canceled |
| Number built | 2 |
| Developed from | Republic F-84 Thunderjet |
The Republic XF-91 Thunderceptor (originally designated XP-91) was a mixed-propulsion prototype interceptor aircraft, developed by Republic Aviation. The aircraft would use a jet engine for most flight, and a cluster of four small rocket engines for added thrust during climb and interception. The design was largely obsolete by the time it was completed due to the rapidly increasing performance of contemporary jet engines, and only two prototypes were built. One of these was the first US fighter to exceed Mach 1 in level flight.
A unique feature of the Thunderceptor, which makes it instantly recognizable, is the odd wing planform which has much greater chord at the tips than the root, the opposite of typical swept wing designs. This was an attempt to address the problem of pitch-up, a potentially deadly problem that plagued early high-speed designs. The Thunderceptor's design meant the entire wing stalled smoothly, more like a straight-wing design.
Design and development
During the development of the XP-84, Republic, under the guidance of Alexander Kartveli looked at the installation of rockets to fighters. The company was inspired by German wartime aircraft: the rocket-powered Messerschmitt Me 163 and the experimental Messerschmitt Me 262C Heimatschützer (home protector) series of interceptor prototypes, which added rocket boosters to a turbojet aircraft.
The Thunderceptor design was one of two swept-wing modifications based on the original Republic F-84 Thunderjet, the other being the Republic F-84F Thunderstreak which was developed later. A serious problem with most swept wing designs of the era was dangerous performance at low speeds and high angle of attack. The stagnant airflow over the wing tended to "slide" towards the wingtips, which caused them to stall before the rest of the wing. In this situation the center of lift would rapidly shift forward relative to the center of mass, pitching the nose up and leading to an even greater angle of attack or, in extreme cases, end-over-end tumbling of the aircraft. Aircraft caught in this regime would often stall and crash, and a rash of such accidents with the North American F-100 Super Sabre led to the term "Sabre dance". The most famous incident was the loss of an F-100C Super Sabre during an attempted emergency landing at Edwards AFB, California on 10 January 1956 which was caught by film cameras set up for an unrelated test. The pilot fought to retain control as he rode the knife-edge of the flight envelope but fell off on one wing, hit the ground and exploded with fatal results.
The Thunderceptor's most notable design feature was intended to address this problem. The wings were built to have considerably more chord (distance from the leading edge to the trailing edge) at the tip than root, allowing them to generate more lift. This neatly addressed the problem of Sabre dance by delaying the point of stall on the tip to that of the entire wing. A side-effect of this design was that the tips had more internal room, so the landing gear was mounted to retract outwards with the wheels lying in the wingtips, using two smaller wheels in a tandem arrangement for each main gear strut, instead of one larger one. Another design change was the ability to vary the angle of incidence of the wing as a whole, tilting it up for low speed operations during takeoff and landing, and then "leveling it off" for high-speed flight and cruise. This allowed the fuselage to remain closer to level while landing, greatly improving visibility.
In keeping with its intended role as an interceptor, the nose was redesigned to incorporate a radar antenna, forcing the air intake for the engine to be moved from its original nose-mounted position to a new intake below it. The fuselage was otherwise very similar to the F-84's. The first prototype did not include the radome, although this was fitted to the second prototype.
Testing and evaluation
The first prototype made its first flight on 9 May 1949, breaking the speed of sound in December 1951. It was later modified with a small radome for gunnery ranging (although not the "full" radome from the second prototype). The second prototype included the full radome and chin-mounted intake, but was otherwise similar. With both the jet and rockets running, the aircraft could reach Mach 1.71. Both prototypes completed 192 test flights over the course of five years.[1]
The second prototype, 46-681, had an engine failure during takeoff from Edwards AFB in the summer of 1951. Republic test pilot Carl Bellinger escaped from the aircraft just as the tail melted off - total flight time was a mere 90 seconds. By the time fire apparatus arrived, driving seven miles across the dry lake bed, the tail section had been reduced to ashes. 46-681 was then fitted with a "V" or "butterfly" tail, and was flight-tested with this configuration. It was later used at Edwards AFB as a crash-crew training simulator, then scrapped.[2]
As an interceptor the Thunderceptor was soon eclipsed by designs from other companies, but like the Thunderceptor none of these would go into production. The United States Air Force decided to wait the short time needed to introduce newer and much more capable designs created as a part of the 1954 interceptor project. The Thunderceptor, like the other interceptor designs of the era, had extremely short flight times on the order of 25 minutes, making them almost useless for protecting an area as large as the United States. The 1954 designs outperformed the XF-91 in speed, range, loiter time, as well as including the radar and fire-control systems needed for night and all-weather operation. The era of the dedicated day fighter-type interceptor was over.
Aircraft disposition
- 46-0680 - Research & Development Gallery at the National Museum of the United States Air Force at Wright-Patterson AFB in Dayton, Ohio.[3]
- 46-0681 - destroyed while testing at Edwards AFB in 1951.[4]
Specifications (XF-91 Thunderceptor)
Data from [citation needed]
General characteristics
- Crew: 1
Performance
- Thrust/weight: 0.60
Armament
- Guns: 4 × 20 mm (.79 in) cannon
See also
Aircraft of comparable role, configuration, and era
Related lists
References
Notes
- ^ Yenne 1993, p. 114.
- ^ Pace 1991, p. 87.
- ^ "XF-91 Thunderceptor/46-680" National Museum of the United States Air Force. Retrieved: 13 June 2011.
- ^ "XF-91 Thunderceptor/46-681." Joe Baugher serial numbers. Retrieved: 10 May 2013.
Bibliography
- Jenkins, Dennis R. and Tony R. Landis. Experimental & Prototype U.S. Air Force Jet Fighters. North Branch, Minnesota, USA: Specialty Press, 2008. ISBN 978-1-58007-111-6.
- Knaack, Marcelle Size.Encyclopedia of US Air Force Aircraft and Missile Systems: Volume 1, Post-World War II Fighters, 1945-1973. Washington, D.C.: Office of Air Force History, 1978. ISBN 0-912799-59-5.
- Pace, Steve. Republic XF-91 Thunderceptor Rocket Fighter (Air Force Legends N.210). Simi Valley, California, USA: Steve Ginter Books, 2000. ISBN 0-942612-91-4.
- Pace, Steve. X-Fighters: USAF Experimental and Prototype Fighters, XP-59 to YF-23. St. Paul, Minnesota, USA: Motorbooks International, 1991. ISBN 0-87938-540-5.
- Winchester, Jim. The World's Worst Aircraft: From Pioneering Failures to Multimillion Dollar Disasters. London: Amber Books Ltd., 2005. ISBN 1-904687-34-2.
- Yeager, Chuck and Leo Janos. Yeager: An Autobiography. New York: Bantam Books, 1986. ISBN 0-553-25674-2.
- Yenne, Bill. The World's Worst Aircraft. New York: Dorset Press, 1993. ISBN 0-88029-490-6.
Further reading
- Pace, Steve (2000). Republic XF-91 Thunderceptor. Air Force Legends. Vol. Nº210 (First ed.). California, United States: Ginter Books. ISBN 0-942612-91-4. Retrieved 1 February 2015.
External links
Wikimedia Commons has media related to Republic XF-91.
- XF-91 in U.S Centennial of Flight Commission
- Several pictures of the XF-91 46-680
- Interceptor, 1949 - pictures from Flight 1949